Monday, April 28, 2008

Friday, April 18, 2008

Documentation on Global warming...

Today Mr. Neo show us a documentary on global warming. The documentary was made by the previous vice president of united states, Albert Arnold 'Al' Gore, Jr. who is a prominent environmental activist. The title of the documentary is "An Inconvinient Truth" which talks about global warming, the causes and effects. Watching the documentary make me realise how we, human takes the nature for granted. We are the one who is destroying the nature and now we have to face the consequences of our action. Global warming is basically the effects of our behavior. Therefore to prevent global warming, we, human have to start appreciate the nature. Just like what Mr. Al Gore said, "it's not a nature issues, It's a moral issues..".

Sunday, April 13, 2008

The Causes..

WHAT IS THE CAUSES??

Carbon Dioxide

From Power Plants
In 2002 about 40% of U.S. carbon dioxide emissions stem from the burning of fossil fuels for the purpose of electricity generation. Coal accounts for 93 percent of the emissions from the electric utility industry. US Emissions Inventory 2004 Executive Summary p. 10. Coal emits around 1.7 times as much carbon per unit of energy when burned as does natural gas and 1.25 times as much as oil. Natural gas gives off 50% of the carbon dioxide, the principal greenhouse gas, released by coal and 25% less carbon dioxide than oil, for the same amount of energy produced. Coal contains about 80 percent more carbon per unit of energy than gas does, and oil contains about 40 percent more. For the typical U.S. household, a metric ton of carbon equals about 10,000 miles of driving at 25 miles per gallon of gasoline or about one year of home heating using a natural gas-fired furnace or about four months of electricity from coal-fired generation.

From Cars
About 33% of U.S carbon dioxide emissions comes from the burning of gasoline in internal-combustion engines of cars and light trucks (minivans, sport utility vehicles, pick-up trucks, and jeeps).US Emissions Inventory 2006 page 8 Vehicles with poor gas mileage contribute the most to global warming. For example, according to the E.P.A's 2000 Fuel Economy Guide, a new Dodge Durango sports utility vehicle (with a 5.9 liter engine) that gets 12 miles per gallon in the city will emit an estimated 800 pounds of carbon dioxide over a distance of 500 city miles. In other words for each gallon of gas a vehicle consumes, 19.6 pounds of carbon dioxide are emitted into the air. A new Honda Insight that gets 61 miles to the gallon will only emit about 161 pounds of carbon dioxide over the same distance of 500 city miles. Sports utility vehicles were built for rough terrain, off road driving in mountains and deserts. When they are used for city driving, they are so much overkill to the environment. If one has to have a large vehicle for their family, station wagons are an intelligent choice for city driving, especially since their price is about half that of a sports utility. Inasmuch as SUV's have a narrow wheel base in respect to their higher silhouette, they are four times as likely as cars to rollover in an accident. The United States is the largest consumer of oil, using 20.4 million barrels per day. In his debate with former Defense Secretary Dick Cheney, during the 2000 Presidential campaign, Senator Joseph Lieberman said, "If we can get 3 miles more per gallon from our cars, we'll save 1 million barrels of oil a day, which is exactly what the (Arctic National Wildlife) Refuge at its best in Alaska would produce." If car manufacturers were to increase their fleets' average gas mileage about 3 miles per gallon, this country could save a million barrels of oil every day, while US drivers would save $25 billion in fuel costs annually.

From Airplanes
The UN's Intergovernmental Panel on Climate Change estimates that aviation causes 3.5 percent of global warming, and that the figure could rise to 15 percent by 2050.
From Buildings Buildings structure account for about 12% of carbon dioxide emissions.

Methane
While carbon dioxide is the principal greenhouse gas, methane is second most important. According to the IPCC, Methane is more than 20 times aseffective as CO2 at trapping heat in the atmosphere. US Emissions Inventory 2004 Levels of atmospheric methane have risen 145% in the last 100 years. Methane is derived from sources such as rice paddies, bovine flatulence, bacteria in bogs and fossil fuel production. Most of the world’s rice, and all of the rice in the United States, is grown on flooded fields. When fields are flooded, anaerobic conditions develop and the organic matter in the soil decomposes, releasing CH4 to the atmosphere, primarily through the rice plants. US Emissions Inventory 2004

Water Vapor in the Atmosphere Increasing
Water vapor is the most prevalent and most poweful greenhouse gas on the planet, but its increasing presence is the result of warming caused by carbon dioxide, methane and other greenhouse gases. (See NOAA's National Climate Data Center (NCDC) FAQ page) Water vapor holds onto two-thirds of the heat trapped by all the greenhouse gases. As the Earth heats up relative humidity is able to increase, allowing the planet's atmosphere to hold more water vapor, causing even more warming, thus a positive feedback scenario. Because the air is warmer, the relative humidity can be higher (in essence, the air is able to 'hold' more water when its warmer), leading to more water vapor in the atmosphere, says the NCDC. There is much scientific uncertainty as to the degree this feedback loop causes increased warming, inasmuch as the water vapor also causes increased cloud formation, which in turn reflects heat back out into space.

Nitrous oxide
Another greenhouse gas is Nitrous oxide (N2O), a colourless, non-flammable gas with a sweetish odour, commonly known as "laughing gas", and sometimes used as an anaesthetic. Nitrous oxide is naturally produced by oceans and rainforests. Man-made sources of nitrous oxide include nylon and nitric acid production, the use of fertilisers in agriculture, cars with catalytic converters and the burning of organic matter. Nitrous oxide is broken down in the atmosphere by chemical reactions that involve sunlight.

Deforestation
After carbon emissions caused by humans, deforestation is the second principle cause of atmospheric carbn dioxide. (NASA Web Site) Deforestation is responsible for 20-25% of all carbon emissions entering the atmosphere, by the burning and cutting of about 34 million acres of trees each year. We are losing millions of acres of rainforests each year, the equivalent in area to the size of Italy. The destroying of tropical forests alone is throwing hundreds of millions of tons of carbon dioxide into the atmosphere each year. We are also losing temperate forests. The temperate forests of the world account for an absorption rate of 2 billion tons of carbon annually. In the temperate forests of Siberia alone, the earth is losing 10 million acres per year.

City Gridlock
In 1996 according to an annual study by traffic engineers [as reported in the San Francisco Chronicle December 10, 1996] from Texas A and M University, it was found that drivers in Los Angeles and New York City alone wasted 600 million gallons of gas annually while just sitting in traffic. The 600 million gallons of gas translates to about 7.5 million tons of carbon dioxide in just those two cities.

Carbon in Atmosphere and Ocean
The atmosphere contains about 750 billion tons of carbon, while 1020 billion tons are dissolved in the surface layers of the world's ocean.

Permafrost
Permafrost is a solid structure of frozen soil, extending to depths of 2.200 feet in some areas of the arctic and subarctic regions, containing grasses, roots, sticks, much of it dating back to 30,000 years. About 25% of the land areas of the Northern Hemisphere hold permafrost, which is defined as soil whose temperature has been 32 degrees Fahrenheit (0 degrees Celsius) for a period of at least 2 years. Permafrost is under 85% of Alaska land surface and much of Canada, Scandinavia and Siberia and holds about 14 per cent of the world's carbon. The hard permafrost on which is built homes and other buildings, can, with rising temperatures, turn into a soft material causing subsidence and damage to buildings, electric generating stations, pipelines and other structures. Ground instability would cause erosion, affect terrain, slopes, roads, foundations and more. Permafrost has acted as a carbon sink, locking away carbon and other greenhouse gases like methane, for thousands of year. But there is now evidence that this is no longer the case, and the permafrost in some areas is starting to give back its carbon. This could accelerate the greenhouse effect.

Tundra
A name very suited to the environs of the arctic and subarctic, tundra means 'treeless plain' in Finnish. The tundra is a biome (a major segment of a particular region having distinctive vegetation, animals and microorganisms adapted to a unique climate), home to about 1700 kinds of plants, including shrubs, mosses, grasses, lichens and 400 kinds of flowers. About 50 billion tons of carbon are estimated to be held in a frozen state in the tundra, and now the tundra is beginning to become a source of carbon dioxide. In the 1970's University of California biologist Walter Oechel studied carbon dioxide emissions in the tundra, which until this time had been thought of as a carbon sink. Doing further tests in the 1980's, Oechel discovered that this was no longer the case, that warming temperatures had changed the tundra to a net emitter of carbon dioxide.

Saturday, April 12, 2008

Global warming...

WHAT IS GLOBAL WARMING???
Global warmth begins with sunlight. When light from the Sun reaches the Earth, roughly 30 percent of it is reflected back into space by clouds, atmospheric particles, reflective ground surfaces, and even ocean surf. The remaining 70 percent of the light is absorbed by the land, air, and oceans, heating our planet’s surface and atmosphere and making life on Earth possible. Solar energy does not stay bound up in Earth’s environment forever. Instead, as the rocks, the air, and the sea warm, they emit thermal radiation, or infrared heat. Much of this thermal radiation travels directly out to space, allowing Earth to cool.


Some of this outgoing radiation, however, is re-absorbed by water vapor, carbon dioxide, and other gases in the atmosphere (called greenhouse gases because of their heat-trapping capacity) and is then re-radiated back toward the Earth’s surface. On the whole, this re-absorption process is good. If there were no greenhouse gases or clouds in the atmosphere, the Earth’s average surface temperature would be a very chilly -18°C (0°F) instead of the comfortable 15°C (59°F) that it is today.
What has scientists concerned now is that over the past 250 years humans have been artificially raising the concentration of greenhouse gases in the atmosphere at an ever-increasing rate. By 2004, humans were pumping out over 8 billion tons of carbon dioxide per year. Some of it was absorbed by “sinks” like forests or the ocean, and the rest accumulated in the atmosphere. We produce millions of pounds of methane by allowing our trash to decompose in landfills and by breeding large herds of methane-belching cattle. Nitrogen-based fertilizers and other soil management practices lead to the release of nitrous oxide into the atmosphere.
Once these greenhouse gases get into the atmosphere, they stay there for decades or longer. According to the Intergovernmental Panel on Climate Change (IPCC), since the industrial revolution began in about 1750, carbon dioxide levels have increased 35 percent and methane levels have increased 148 percent. Paleoclimate readings taken from ice cores and fossil records show that these gases, two of the most abundant greenhouse gases, are at their highest levels in at least the past 650,000 years. Scientists have very high confidence (a phrase the IPCC translates to “greater than 90 percent certainty”) that the increased concentrations of greenhouse gases have made it more difficult for thermal radiation to leave the Earth, and as a result, Earth has warmed.

Thursday, April 10, 2008

Global warming...

Our tasks for assignment 3 is a poster with a statement based from global warming. Therefore, i need to find the information and start my sketch for the poster. Oh yea, we also need to have a web-documentation, which carries 10 percent of the marks!! I'll upload the info soon!

Tuesday, April 8, 2008

Tuesday, April 1, 2008

Research..

Few photo from deepavali celebration !!






Festival of lights!

Finally, i decided to do on deepavali..my statement will be "deepavali is a festival of lights!". From what I know, deepavali is very colourful festival or "ranggoli" as they said. However, actually deepavali is a festival of lights ,where the lights or lamps signify victory of good over the evil within every human being. It is usually celebrate by the Hindus, Jains and Sikhs. It is a federal public holiday throughout Malaysia. I've done the sketch already. I'll upload it soon!!! Btw, deepavali is on the october 28th this year..